Self-hardening alloy or iron and steel.



UNITED STATES PATENT oFFIon.

No. 832,733. a

Specification of Letters Patent.

SELF-HARDENING ALLOY OF mom AND STEEL. I

Patented Oct. 9, 1906 Application filed Kay 17, 1906. Serial No. 317,847.

To all whom it may concern: Be it known that I, JAMES CHURCHWARD, a subject of the Kin of Great Britain, residing in the borough Manhattan,- in the city, county, and Stateof New York, have invent-- ed certain new and useful Improvements in Self-Hardening Alloys of Iron and Steel, of

which the following is a specification.

The present invention relates to alloys of iron and steel, and particularly the latter, where nickel is employed as one of the alloying metals; and the object of the invention is to produce a self-hardening metal, as will be hereinafter described, whichwill be suitable for many uses and urposes. A

In carryin out t e present invention there is mixed wit pure refined iron or steel relatively small proportions of nickel, tungsten, chromium, manganese, and vanadium, and the allov is melted and cast into the proper shapes.

A suitable proportion of the several metals for producing a self-hardening tool-steel will be understood from the following formula, in

2 5 which the proportions are designated in percentages' by weight: pure steel, containing sixty per cent. carbon, ninety; nickel, five; tungsten, one; chromium, 2.50; manganese, one; .vanadium, 0.50; total, one hundred.

The carbon may be added to the iron or steel in many known ways, and it. may vary from .20 to 1.0 per cent., according to the uses to which the allo is to be applied. The

ercenta es of the al oying metals may also e varie to some extent for the same reason.

For example, these metals may vary in proportion as follows: steel, from eighty-four to ninety per cent; nickel, fromfour to six per cent. tungsten, from 0.5 to 1.5 per cent. chromium, from 2.5 to three per cent. manganese, from 0.5 to-one per cent. and vanadium, from 0.25 to 0.5 er cent.

It is believed that t e .allo elements named react on each other to ro uce chemical and molecular changes of such a nature that the tungsten, chromium, and man anese are permitted to harden the steel, while the vanadium removes or prevents brittleness andimparts toughness without softenin the alloy. Ferro com ounds of the severa alloying metals may. e used in lieu of the pure meta Having thus described my invention, I claim- An allo composed of the following metals in about t e roportions given, name y: steel, containing a out .20 to .60 per cent. of carbon, eighty-four to ninety per cent.; nickel, four to six per cent. tungsten, 0.5 to 1.5 per cent.; chromium, 2.5 to three per cent; man- 60 ganese, 0.5 to one per cent., and vanadium 0.25 to 0.5 per. cent.

In witness whereof'I have hereunto signed my name, this 16th .dayof May, 1906, in the presence of two subscrlbing witnesses.

JAMES OHURCHWARD. 

